Push button switch construction



July 15, 1941.

J. c..1oo'sr ETAL PUSH BUTTONSWI--TCH CONSTRUCTION Filed 1u-1y 15J 1959- 2 sheets-sheet 1 July 15, 1941. J. c. JoosT Erm.

PUSH BUTTON SWITCH CONSTRUCTION Filed July 15, 1939 2 Sheets-Sheet 2 RTL Y 05M M ma WR 10 .o @JN I N64 T s. @n YW 6B Patented July 15, 1941 PUSH BUTTON SWITCH CONSTRUCTION John C. Joost, Mount Vernon, N. Y., and Christian Miller, Norwalk, Conn., assignors to Edwards and Company, Inc.. Norwalk, Conn., a corporation of New York Application July 15, 1939, Serial No. 284,670

i Claims.

This invention relates to the construction of switches intended primarily for installation in alarm or signalling systems where the switch is to be actuated by a moving or movable part such as a window, transom, door of a building or room or the like, or a door of a safe or strong box, or other closure member.

@ne of the objects of this invention is to provide a durable, strong and compact switch construction of the above-mentioned character that will be capable of dependable actuation in spite of widely varying conditions met with in practice, such as for example differences in clearance between a window and its frame, or between a door and its door jamb, or the like. Another object is to provide a simple and inexpensive switch construction that may be easily and quickly installed and that will have structural and functional characteristics which will insure intended operation by the movable part such as the window or door, without requiring readjustment' of the parts or compensation for variations in play or clearance met with inpractice or more than the skill of the usual mechanic. Another object is to provide a construction of the abovementioned character which will be capable of inexpensive manufacture of individualparts and capable of inexpensive assembly, while also having wide exibility of functional characteristics to meet various conditions of practical use. Another object is to provide a switch construction of the above-mentioned character which can be made, in a simple and inexpensive manner, to meet widely varying circuit requirements such as are met with in various types of signalling or alarm circuits wherein for example a normally closed circuit is to be interrupted, or a normally open circuit is to be closed, or where the circuit is to be only momentarily closed or as in other systems only momentarily broken.

Another object is to provide a push button switch construction that will be strong and durable, of compact construction, of dependable action, and capable of wide variation, according to requirements met with, in sensitiveness or speed of response, or of variation in character of circuit control effected. Another object is to provide a switch construction of the push type wherein, in a simple and inexpensive manner. the character and number or repetition of circuit-making or circuit-breaking may be widely varied to suit the particular practical requirements. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts as will be exemplifled in the structure to be hereinafter described and the scope of the application of which will be indicated in the following claims.

in the accompanying drawings in which is shown one of the various possible embodiments of our invention,

Figure 1 is a front elevation of the struction;

Figure 2 is a side elevation thereof but also showing an illustrative installation thereof;

Figure 3 is a vertical sectional view, on an enlarged scale, as seen along the line 3-3 of Figure 1;

Figure 4 is a rear end view as seen from the rear in Figure 1; and

switch con- Figures 5, s, '1, s, 9 and 1o are detached frag-- mentary elevations showing illustrative or possible rearrangements of certain of the internal parts for achieving different kinds of circuit controis.

Similar reference characters refer to similar parts throughout the several views of the drawings.

Referring first to Figures 2 and 3, the switch construction comprises preferably a housing or shell 20, preferably in the form of a sleeve or cylinder and preferably open at both ends, having secured thereto or integrally formed therewith at the front end a front plate 2| adapted to rest against the face 22 (Figure 2) of the part indicated at 23 with respect to which the switch structure is to be mounted, the shell 20 being accommodated preferably in a hole 24 controlled or otherwise formed in the member 23, while suitable securing means such as screws 25 passing through suitable holes in the plate 2| may be employed to hold the construction securely in place. The part 23 of Figure 2 might be considered to be preferably any suitable stationary part, such as a door frame or window fratrie with respect to which a closure indicated at 26, such as a door, window or the like, is mounted for movement such as into or out of closing position. In Figure 2 we have purposely shown a gap or clearance 21 between the parts 23 and 26 to indicate one of widely varying degrees of clearance or of misfit that have to be copied with in practice. For example if the part 26 is a window, it might nt in its frame with comparative snugness or with a looseness or play that might approximate 1A". Or if the part 26 is a door, warpage or shrinkage or other change might bring about similar wide variations in nt between the door and the door frame. And also an initial amount of play or clearance or lack of it might, in course of time, due to such factors as distortion, settling, shrinking or the like be converted into something quite different. But according to certain features of our invention we achieve intended circuit control in spite of such wide variations in factors such as those noted above.

Projecting outwardly from the shell 23 and beyond the plane of the front face of the mounting plate or flange 20 is a large operator 23 having its outer or exposed face preferably cam shaped, illustratlvely and preferably having an external frusto-conical surface 23* terminating at its outer end in a substantially rounded over or spherical end surface 28h, the dimension of length of the operator 28 in the direction of the axis of the cylindrical shell 20 and with which it is coaxial being preferably slightly greater than the maximum clearance or gap 21 (see Figure 2) that is to be met with in practice; illustratively this dimension might be on the order of or 1/2".

The right-hand or inner end of the operator 28 has a cylindrical extension or sleeve 23 which extends into the shell 23 preferably and illustratively throughout about half of the axial length of the shell 23, making a sliding fit with the shell 23. The sleeve 23, if thus dimensioned, dependably guides the operator 23 for movement axially of the shell 20 and against tilting; in some forms of installation, the movable part 26 (Figure 2), instead of exerting a push on the operator 28 in the direction of its axis, may engage the cam shaped face 28, as for example when the part 26 is a sliding window slldable downwardly from the position shown in Figure 2, the cam surface resolving the downward thrust into a horizontal component to force the operator 28 to the right as viewed in Figures 2 and 3, any vertical or downward componentl being dependably resisted and withstood by the relatively large bearing surfaces between the sleeve 23 and the shell 20. Like the parts 20 and 2i, the operator 28 with its sleeve extension 29 may be made integral and are preferably made of a suitably heavy sheet metal or casting or a screwmachine part.

The operator 28 has a hole 30 in its axis and at its apex to receive the reduced or stepped end 3F* of a preferably cylindrical metal rod that has a stepped portion 3i.b that terminates preferably in the plane of the inner end of the sleeve 29 (Figure 3), and an end portion 3| that terminates somewhat beyond the end of the shell 20. The rod 3| may be secured in the hole 30 in any suitable way, as by threading, but preferably as by riveting or heading over or expanding the outer end of the reduced end portion 3Ia; it is thus assembled to the part 28-23 after Stringing on to the stepped part 3ib and, preferably throughout its entire length, washers 32 of a suitable non-conductive material like fiber and washers 33 of metal such as brass. These Washers are of simple and inexpensive construction, are preferably all of the same size and also snugly tted to the rod part Bib, thus lpresenting an external cylindrical surface, concentric with the inside faces of the parts 28-29 and also spaced from the latter, that is thus made up of conductive parts and non-conductive parts. Washers 33 are preferably insulated from rod 3i by insulating bushings 33, one force-fitted into each washer.

With the cylindrical surface thus built up and which partakes of the movement to which the operator 23 is subjected, coacts certain contact means which preferably comprises two contact springs or brushes 34-33, made preferably of a flat sheet material having spring characteristics, such as phosphor-bronze, whose inner or lefthand ends are preferably slightly curved as shown in Figure 3 and are, by the springiness of the material, urged inwardly toward each other and thus pressed, from opposite sides, against the cylinder built up of the washers 32-33.

It is preferably to these brush contacts 34-3l that the external circuit is connected by suitable terminal connectors, and a preferred construction for achieving such electrical connections and also for mounting the brush contacts 34--33 dependably in position is like that shown better in Figure 4.

Turning now to Figure 4 we prefer to terminate the end of the shell 2l in, or otherwise to provide it with, suitably spaced bendable ears, illustratively two in number as at 36-31. A disk-like member 33 of insulating material like bre is of a diameter substantially matching the outside diameter of the shell 23, being cut away as at 38* and 33b to by-pass the ears 38 and 31 to permit ultimate assembly thereof to the end of the shell 23. It is slotted or apertured as at 33 and 43 (Figure 4), for the passage therethrough of the brush contacts 34 and 33 respectively, the latter having integrally formed therewith end plates 34 and 35* respectively, which extend at right angles thereto and thus flat-wise against the rear face of the insulating disk 23, each end plate having an aperture 34b and Iiih at an end thereof and registering with respective underlying apertures in the member 33.

Against these end plates 34 and 35* of the contact brushes rest respectively the base plate portions 42a and 43 of terminal connector elements 42 and 43 respectively, which have upstanding therefrom post-like portions 42b and 43b respectively and into which are threaded the screws 44 and 45 by which the two conductors of the circuit may be respectively anchored mechanically and electrically connected.

The end plates of the Contact brushes and the base plates of the terminal connectors preferably have substantially symmetrical shapes, as is indicated in Figure 4, thus providing large contact areas therebetween and insuring secure fastening thereof to the insulating member 33. Thus base plate 42 is preferably secured to the member 38 by a rivet in the form of an eyelet 46, whose one end thus becomes exposed upon the inner face of the member 33, the plate portion 34 of the contact brush 34 becoming securely clamped under the part 42. The latter preferably has a prong 42 which passes through the hole 34b in the plate 34 and extends into a hole in the insulating member 33, thus preventing rotary displacement of either the part 42 or the part 34 about the axis of the rivet 48.

In a similar way an eyelet 41 clamps the parts 43 and 35n against the outer face of the member 38, part`43t having a prong 43c that passes through the hole 35b in'the end plate 35* and enters a hole in the member 33 to prevent rotary displacement of this mounting. These various parts, thus related to the member 33 may be assembled as Just described and form with the part 33 a sub-assembly.

Part 33 has a central hole 33c of a diameter sufficient to pass the large end 3I of the rod 3i therethrough, and it may now be assembled to the rear endV of the shell 20, but preferably because of the exposed ends of the eyelets I--'l there is first positioned against the inner face of the member 38 a thin insulating washer W suitably apertured however to permit the brush contacts 24-25 to pass therethrough and also to have an aperture to mate with the hole 2l, being also cut away to accommodate the lugs or ears and 8l. This assemblage is rested against the end edges of the shell 20 as shown in'Figure 3, whence the ears 3B and Il are bent over against the member 28 to clamp it and the washer Il rigidly and securely in closing position with respect to the rear end ofthe shell 20.

A helical spring ll, of an inside diameter materially greater than vthe maximum transverse space occupied by the contact brushes "-35 may now be inserted into the shell from its front end, so that it extends about the brush contacts 34-25 with its one end resting against the washer lll, which thus prevents the spring from contacting with the heads of the rivets 46--41 The operator 28 with the rod 3| and washers 32-33 assembled to it as above described and thus forming another sub-assembly is now put in position, the large end llc of the rod 3l passing through the registering holes in the end disks 50--38 and sleeve 29 sliding into the shell 20, the forward end portion of the spring entering the sleeve 2l which is preferably shouldered as at 29 to form an abutment against which the front end of the spring El bears, the latter being compressed during this assembly operation.

With the rear end of rod 3| projecting beyond the end disk 38, suitable means are now employed to prevent withdrawal of this sub-assembly from the shell 20. Preferably the endmost portion of the rod 3| is provided with a peripheral recess or groove 3ld to receive a split spring ring or washer 52 (Figures 3 and 4), thus to take up the thrust of the spring 5I in an outward direction and to coact with the spring in holding the parts in their normal positions as shown in Figure 3. The device is now ready for installation in the manner already above described.

With the parts in normal position as shown in Figure 3, the brush ends of the contact members 34-35 preferably engage only the one or two washers at the right-hand end of the rod part 3l. If actuation of the operator 2B is to close the circuit, these endmost washers with which the brush is normally in contact are the insulating washers 32 as shown in Figure 5, the immediately succeeding washer and the rest of the washers being in the form of washers 33 which are conductive. With such arrangement the slightest initial actuation of operator 28 closes the circuit and the circuit is maintained closed throughout any and all subsequent displacement of the operator 28 against the action of the spring 5l.

If the just-described characteristics of operation are desired in a normally closed circuit. the endmost one or two washers with which the brushes 34-35 normally engage are conductive washers 33 as in Figure 6. the immediately succeeding washer and the rest of them being nonconductive washers 32. Thus the slightest actuation of operator 28 opens the circuit and maintains it open throughout in subsequent displacement of the operator against the action of the spring 5l.

Also it will be noted that these results are dependably achieved irrespective of wide variation in the amount of play, looseness or clearance indicated at 21 in Figure 2 and also described above. For example if the fit of the parts 22 and 2l is snug, the operator 2l is given a maximum inward displacement; should the play be substantial at the gap 21, approximating the amount that the operator 28 projects from the plane of the surface 22 (Figure 2), the displacement of the operator is much less and may be only very slight, yet the above actions are dependably assured.

Should the circuit arrangement be such that only a momentary make and break in the circuit is desired, the washer or disk members strung on to the rod part 2lb may be arranged as in Figure 7; thus the one or two washers normally contacted by the brushes N- are in the form of insulating washers 22, whence the immediately succeeding washer is conductive washer 33, the remaining washers being non-conductive washers 32. Here a displacement of operator 28 by an amount only slightly greater than the thickness of the conductive washer 23 suilces momentarily to make the circuit, immediately interrupting it. If desired of course greater 1atitude may be provided by substituting for the single conductive washer 33 washers of diilerent thicknesses or two or more conductive washers. If an analogous effect is desired in the closedcircuit type of system, an arrangement like that of Figure 8 may be utilized, that being, as will now be understood, an interchange of conductive and non-conductive washers as compared with the arrangement of Figure 7.

Also there are circumstances where a succession or repetition of make-and-break operations or of break-and-make operations are desirable; in the former case, a possible arrangement is indicated in Figure 9 and in the latter case an illustrative arrangement is shown in Figure 10. Here the bridging conductive washers are a1ternated either singly or in groups with non-conductive Washers, either singly or in groups, so that each stroke of the operator 28 changes the circuit conditions several times. These washers may be made up in very small dimensions, a

goodly number, as appears from Figure 3, may be accommodated on the rod part 3lb, and thus a series of many circuit changes may be effected for each stroke. For example there are certain types of audible signalling devices such as a chime or a gong where simplicity and inexpensiveness of construction, or other factors, dictate a signal production as a result of only a single stroke resulting from a single push button switch actuation; but by utilizing an arrangement like that of Figure 9, a single'manual manipulation of the operator 28, namely to depress it and upon release to let it return, may be made to effect repeated energizations of the signalling device and thus cause it to give a number of strokes where, under prior practices, only a single stroke could be achieved.

Thus it will be seen that there has been provided in this invention a switch construction in which the several objects herein-before noted together with many thoroughly practical advantages are successfully achieved. It will be seen that the construction is strong, durable and inexpensive, yet is of efficient action under widely varying conditions of practice, and also, where desired, is of such flexibility of arrangement as to meet in a simple and inexpensive way a wide variety of electrical circuit requirements.

As many possible embodiments may be made oi' the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:

l. A switch construction of the character described, comprising a cylindrical shell having means for .mounting it on a suitable support, said shell having means at its rear end for insulatingly mounting contact-connector means having a connector element exposed externally of the shell and having a contact brush extending inwardly of the shell and toward the front end thereof, said rear mounting means having an aperture positioned substantially in line with the axis of said shell, a spring-opposed operator having a hollow cylindrical extension slidably iltted into the shell with its inner end terminating, when said operator is in normal position, in spaced relation to said mounting means, a rodlike member secured at one end to said operator and having its other end extended through said aperture in said rear mounting means, said rod member having means forming a shoulder spaced from the inner end face of said operator and carrying between the latter and said shoulder means a plurality of insulating and conductive members strung thereon, and held therebetween, at least certain of said members being of small axial dimension as compared to the stroke of movement of said operator, and said contact brush being positioned at the end of a radius from the axis of said shell that is less than the radius of said hollow cylindrical extension so that, upon actuation of said operator, said hollow cylindrical extension may freely envelop said contact brush, the latter engaging said insulating and conductive members successively as said operator is actuated to effect sliding movement thereof and hence of said rod member relative to said shell.

2. A construction as claimed in claim 1 in which said operator normally projects beyond the front end of said shell and is hollow, said rod-like member extending into the hollow of said operator I and thereby accommodating therein insulating and conductive members, the said contact brush being of a length suflicient to bring insulating or conductive members within said hollow operator into engagement therewith upon actuation of the operator inwardly of said shell.

3. A construction as claimed in claim l in which said operator is hollow and in normal position bulges outwardly from the front end of said shell, said rod-like member extending into the hollow of said operator thereby to accommodate insulating or conductive members therein, said brush being of sufficient length in` a direction toward the iront end of said shell to be engaged by insulating or conductive members within the hollow operator, the spring for opposing said operator being a helical spring of an internal radius of curvature greater than the radius from the axis of said shell to the outermost part of said contact brush so as to envelop with suincient clearance the latter and said rod member and members carried by the latter and being interposed between said operator and said rear mounting means.

4. A switch construction comprising two telescoping members, one of which is a. casing shell and the other of which is an operator shell slidably and telescopically received into the front end of said casing shell, said two shells encompassing a space of substantial cross-sectional area transversely of the axis along which said operator shell telescopically slides relative to said casing shell and of a length in the direction of said axis variable according to the telescopic movement of said operator shell relative to said pasing shell, means limiting sliding movement outwardly, and thereby fixing the normal position, of said operator shell, said casing shell having means at its rear end for insulatingly mounting contact-connector means having conductorconnector means exposed externally of the shell and having contact brush means extending inwardly from said rear end and into said space,-

said brush means being oi' a length shorter than the maximum length of said space as fixed by said limiting means and extending intermediate of said axis and of the lateral walls of said telescoping shells, said operator shell carrying, in alinement with said axis, circuit-controlling means comprising at least two successively arranged members one of which is conductive and the other of which is non-conductive for coaction with said brush means, said brush means, when said operator shell is in said normal position, engaging the innermost of said two members, the junction between said two members being spaced from the point of contact of said brush means with said innermost member, when said operator shell is in said normal position, by a distance that is-small in comparison to the range of movement inward of said-operator shell, whereby in response to movement inwardly of said operatorshell by an amount at least equal to said distance said junction is moved beyond said point of contact, and a coil spring 'opposing inward telescopic movement of said operator shell and holding it in normal position relative to said casing shell, the coils of said spring being of a diameter to be accommodated in said space and about but out oi' contact with said brush means and said circuit-controlling means.

5. A switch construction comprising two telescoping members, one of which is a casing shell and the other of which is an operator shell slidably and telescopically received into the front end of said casing shell, said two shellsencompassing a space of substantial cross-sectional area transversely of the axis along which said operator shell telescopically slides relative to said casing shell and of a length in the direction of said axis variable according to the telescopic movement of said operator shell relative to said casing shell, said casing shell having means at its rear end for insulatingly mounting contactconnector means having conductor-connector means exposed externally of the shell and having contact brush means extending inwardly from said rear end and into said space, said brush means beingoi a length shorter than the maximum length of said space and extending intermediate of said axis and of the lateral walls of said telescoping shells, said rear mounting means having an aperture positioned substantially in line with said axis, a rod-like member secured at one end to said operator shell and extending substantially in line with said axis through said aperture in said rear mounting means and having strung thereon a plurality of washer-like insulating and conductive members for sliding contact, upon telescopic movement of said operator shell relative to said casing shell, with said brush means, said washer-like members being in dimension transversely of said axis less than the transverse dimension oi' said space, and a coil spring for opposing inward telescopic movement of said operator shell relative to said casing shell having turns of a diameter to extend about but free from contact with said washer-like members and said brush means.

6. A switch construction comprising two telescoping members, one of which is a casing shell and the other of which is an operator shell slidwbly and telescopically received into the iront end of said casing shell, Ysaid two shells encompassing a space of substantial cross-sectional area transversely of the axis along which said operator shell telescopically slides relative to said casing shell and of a length in the direction of said axis variable according to the telescopic movement of said operator shell relative to said casing shell, said casing shell having means at its rear end for insulating mounting contact-connector means having conductor-connector means exposed externally of the shell and having contact brush means extending inwardly from said rear end and into said space, said brush means being of a length shorter than the maximum length of said space and extending intermediate oi said axis and of the lateral walls-of said tele' scoping shells, said operator shell carrying, in alinement with said axis, circuit-controlling means for coaction with said brush means in response to relative telescopic movement between said shell members, and a coil spring opposing inward telescopic movement of said operator shell relative to said casing shell, the coils of said spring being oi a diameter to be accommodated in said space and about but out of contact with said brush means and said circuit-controlling means, the end wall of said operator shell bulging outwardly in the direction of said axis and forming inwardly of said operator shell an extension of said space to accommodate end portions of said brush means upon inward telescopic movement of said operator shell relative to said casing shell.

'7. A switch construction as claimed in claim 5 in which the end wall of said operator shell ex-` tends outwardly in the direction of said axis and forms internally thereof an extension of said space, said rod-like member extending through said extension and said extension accommodating at least some of said plurality of washerlike members with suilicient space about the washer-like members accommodated in said extension to also accommodate at least end portions of said brush means upon suilicient inward telescopic movement of said operator shell relative to said casing shell.

JOHN C. JOOST. CHRISTIAN MILLER.

CERTIFICATE OF CORRECTION.

,Patent No. 21,249,001. July' l5, 19141.

JOHN C. JOOST, ET AL.

It is hereby certified that error appears in the printe specification of the above numbered patent requiring correction as follows: Page l, second column, line 11.9, for the word "'copied" read coped-`; page 2, first column, line 16, for "of" after "dimension" read or; page 5, first column, line 18, claim 6, for "insulating" read -insu1atinglyf; and that the said Letters 4Patent should be read with this correction therein that the same. may conform. to the record of the vcase in the Patent Office.

Signed andv sealed this 2nd day of September, A. D. l9lll.

Henry VanjArsdale, "(Seal) Acting Commissioner' of Patents.

CERTIFICATE OF CORRECTION.

,Patent No. 21,249,001. July' l5, 19141.

JOHN C. JOOST, ET AL.

It is hereby certified that error appears in the printe specification of the above numbered patent requiring correction as follows: Page l, second column, line 11.9, for the word "'copied" read coped-`; page 2, first column, line 16, for "of" after "dimension" read or; page 5, first column, line 18, claim 6, for "insulating" read -insu1atinglyf; and that the said Letters 4Patent should be read with this correction therein that the same. may conform. to the record of the vcase in the Patent Office.

Signed andv sealed this 2nd day of September, A. D. l9lll.

Henry VanjArsdale, "(Seal) Acting Commissioner' of Patents.

Patent No. 2,214.9,00L

CERTIFICATE OF CORRECTION. v

, July' l5, '19111'. JOHN c. JOOST., ET AL.

It is hereby certified that error appears in the printed specification .ofthe above numbered patentrequiring correctionas follows: Page l, seco nd column, line )4.9, for the word "copied" read coped page 2, first column, line 16, for "of" after "dimension" read or; page 5, first co1- ungn, line 18, claim 6, for "insulating" read insu1ating1y and that the said Letters -Patent should be read with this correction therein that the same. may conform. tothe record ofthe .c ase in the Patent Office.

' Signed and sealedl this y2nd day of September, A. D. 19141.

Henry VanjArsdale, "(lseal) Acting Connnission'er' of Patents. 

